Molecular spectroscopy assignment

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KIM 4106 SEM 1 18/19
ASSIGNMENT
QUANTUM ORIGIN OF LIFE
NAME : SARMILLA SREE A/P MUNIANDY (S43906)
PROGRAMME : BACHELOR OF SCIENCE (CHEMICAL SCIENCES)
LECTURER’S NAME: PROF DR KU HALIM BIN KU BULAT
Quantum Origin of Life
Some defines life as an illusion and some defines as the living matter and, as such, matter that
shows certain attributes that include responsiveness, growth, metabolism, energy transformation
and reproduction. Although there is no agreement in definition of life, Davies said that all living
things are information processors whereby they store a genetic database and replicate it, with
occasional errors, thus providing the basis for natural selection. The great scientist, Schrödinger
also argued that the stable transmission of genetic information from generation to generation in
discrete bits implied a quantum mechanical process, although he was unaware of the role of or the
specifics of genetic encoding in 1944.
Biological molecules do not only specialized in chemical role but they are also specialized in
informational role. In recent years our understanding of the nature of information has undergone
something of a revolution with the development of the subjects of quantum computation and
quantum information processing. The starting point of this enterprise is the replacement of the
classical “bit” by its quantum counterpart, the “qubit”. As a quantum system evolves, information
is processed, stated by Davies, 2003.
In the case of familiar DNA based life, the information represented by the base-pair sequence such
as adenine, guanine, tyrosine and cytosine are replicated together. Thus information replication is
tied to structural replication. But at the quantum level there are alternative possibilities. Consider,
for example, a cellular automaton, such as the Game of Life.
One of the great question of biology is, to synthesise these informative molecules, all we need is
only 13 amino acids. Then why the genetic basis in life involves 20 amino acids? An international
team of researchers has created a quantum chemistry models that explains what triggered the
inclusion of the additional 7 amino acids in 2018. A spike in the levels of oxygen in our biosphere,
coupled with the discovery that the newer amino acids have a greater chemical reactivity than the
older ones.
Moosmann and his colleagues created a quantum chemistry model that compared amino acids on
Earth to amino acids from space that had arrived via meteorites. There's less to react to out in space
than there is on Earth, so while in space the handful of older amino might suffice, life inside
our atmosphere required a little extra help. The researchers found that the younger the amino, the
more reactive it is to external forces, making it more adaptable—an advantage in pretty much
anything involving the evolutionary process.
The researchers conducted additional experiments which verified their theoretical results.
They found that at least three of the newer amino such as methionine, tryptophan and
selenocysteine that were included in response to the rising levels of oxygen in our atmosphere. We
find that the energetic HOMO–LUMO gap, a correlate of chemical reactivity, becomes
incrementally closer in modern amino acids, reaching the level of specialized redox cofactors in
the late amino acids tryptophan and selenocysteine due to evolutionary position in the genetic
code. (Granold et al., 2018).
This results in primordial life to deploy increasingly soft molecules such as in mammals and fungi.
References
Davies, P. C. W. (1953). A Quantum Origin of Life ? Molecular Biology, 3–18.
https://doi.org/10.1142/9781848162556_0001
Granold, M., Hajieva, P., Toşa, M. I., Irimie, F.-D., & Moosmann, B. (2017). Modern
diversification of the amino acid repertoire driven by oxygen. Proceedings of the National
Academy of Sciences, 115(1), 201717100. https://doi.org/10.1073/pnas.1717100115